Agreement Between Child Self-report and Caregiver-Proxy Report for Symptoms and Functioning of Children Undergoing Cancer Treatment

IMPORTANCE Adult patients are considered the best reporters of their own health-related quality of life (HRQOL). Self-report in pediatrics has been challenged by a limited array of valid measures. Caregiver report is therefore often used as a proxy for child report. OBJECTIVES To examine the degree of alignment between child and caregiver proxy report for Patient-Reported Outcomes Measurement Information System (PROMIS) HRQOL domains among children with cancer and to identify factors associated with better child and caregiver-proxy congruence. DESIGN, SETTING, AND PARTICIPANTS In this multicenter cohort study, children with a first cancer diagnosis and their caregivers completed surveys at 2 time points: within 72 hours preceding treatment initiation (T1) and during follow-up (T2), when symptom burden was expected to be higher (eg, 7-17 days later for chemotherapy). Data were collected from October 26, 2016, to October 5, 2018, at 9 pediatric oncology hospitals. Five hundred eighty children (aged 7-18 years) and their caregivers were approached; 482 child-caregiver dyads completed surveys at T1 (response rate 83%), and 403 completed surveys at T2 (84% of T1 participants). Data were analyzed from July 1, 2019, to April 22, 2020. EXPOSURES Participants received up-front cancer treatment, including chemotherapy and radiotherapy. MAIN OUTCOMES AND MEASURES Congruence between child self-report and caregiver-proxy report of PROMIS pediatric domains of mobility (physical functioning), pain interference, fatigue, depressive symptoms, anxiety, and psychological stress. RESULTS Of the 482 dyads included in the analysis, 262 children (54%) were male (mean [SD] age, 12.9 [3.4] years), 80 (17%) were Black, and 71 (15%) were Hispanic. Intraclass correlations between child self-report and caregiver proxy report showed moderate agreement for mobility (0.57 [95% CI, 0.50-0.63]) and poor agreement for symptoms (range, 0.32 [95% CI, 0.24-0.41] for fatigue to 0.42 [95% CI, 0.34-0.50] for psychological stress). Children reported lower symptom burden and higher mobility than caregivers reported. In a multivariable model adjusted for child and parent sociodemographic factors and the caregivers own self-reported HRQOL, caregivers reported the childs mobility score 6.00 points worse than the childs self-report at T2 (95% CI, -7.45 to -4.51), exceeding the PROMIS minimally important difference of 3 points. Caregivers overestimated the childs self-reported symptom levels, ranging from 5.79 (95% CI, 3.99-7.60) points for psychological stress to 13.69 (95% CI, 11.60-15.78) points for fatigue. The caregivers own self-reported HRQOL was associated with the magnitude of difference between child and caregiver scores for all domains except mobility; for example, for fatigue, the magnitude of difference between child and caregiver-proxy scores increased by 0.21 (95% CI, 0.13-0.30) points for each 1-point increase in the caregivers own fatigue score. CONCLUSIONS AND RELEVANCE This study found that caregivers consistently overestimated symptoms and underestimated mobility relative to the children themselves. These results suggest that elicitation of the childs own report should be pursued whenever possible.